diff --git a/src/lib/app.ts b/src/lib/app.ts
index f3c1483904..2d407d7405 100644
--- a/src/lib/app.ts
+++ b/src/lib/app.ts
@@ -197,10 +197,6 @@ export default async function getApp(
     // Setup API routes
     app.use(`${baseUriPath}/`, new IndexRouter(config, services, db).router);
 
-    if (services.openApiService) {
-        services.openApiService.useErrorHandler(app);
-    }
-
     if (process.env.NODE_ENV !== 'production') {
         app.use(errorHandler());
     } else {
diff --git a/src/lib/routes/controller.ts b/src/lib/routes/controller.ts
index d9ba28aa2f..0b3f36f153 100644
--- a/src/lib/routes/controller.ts
+++ b/src/lib/routes/controller.ts
@@ -10,6 +10,7 @@ import { type IUnleashConfig, NONE } from '../types';
 import { handleErrors } from './util';
 import requireContentType from '../middleware/content_type_checker';
 import { PermissionError } from '../error';
+import { fromOpenApiValidationErrors } from '../error/bad-data-error';
 import { storeRequestedRoute } from '../middleware/response-time-metrics';
 
 type IRequestHandler<P = any, ResBody = any, ReqBody = any, ReqQuery = any> = (
@@ -64,6 +65,16 @@ const checkPrivateProjectPermissions = () => async (req, res, next) => {
     return res.status(404).end();
 };
 
+const openAPIValidationMiddleware = async (err, req, res, next) => {
+    if (err?.status && err.validationErrors) {
+        const apiError = fromOpenApiValidationErrors(req, err.validationErrors);
+
+        res.status(apiError.statusCode).json(apiError);
+    } else {
+        next(err);
+    }
+};
+
 /**
  * Base class for Controllers to standardize binding to express Router.
  *
@@ -114,6 +125,8 @@ export default class Controller {
             this.useContentTypeMiddleware(options),
             this.useRouteErrorHandler(options.handler.bind(this)),
         );
+
+        this.app.use(options.path, openAPIValidationMiddleware);
     }
 
     get(
diff --git a/src/lib/services/openapi-service.ts b/src/lib/services/openapi-service.ts
index f678bfb413..4cec326990 100644
--- a/src/lib/services/openapi-service.ts
+++ b/src/lib/services/openapi-service.ts
@@ -11,7 +11,6 @@ import type { ApiOperation } from '../openapi/util/api-operation';
 import type { Logger } from '../logger';
 import { validateSchema } from '../openapi/validate';
 import type { IFlagResolver } from '../types';
-import { fromOpenApiValidationErrors } from '../error/bad-data-error';
 
 export class OpenApiService {
     private readonly config: IUnleashConfig;
@@ -60,21 +59,6 @@ export class OpenApiService {
         });
     }
 
-    useErrorHandler(app: Express): void {
-        app.use((err, req, res, next) => {
-            if (err?.status && err.validationErrors) {
-                const apiError = fromOpenApiValidationErrors(
-                    req,
-                    err.validationErrors,
-                );
-
-                res.status(apiError.statusCode).json(apiError);
-            } else {
-                next(err);
-            }
-        });
-    }
-
     respondWithValidation<T, S = SchemaId>(
         status: number,
         res: Response<T>,